Abstract: A polygonal mirror apparatus with an improved installation structure of a polygonal mirror, which is made using a plastic material, with respect to a rotor frame. The polygonal mirror apparatus includes a base, and a bearing coupled to the base and having a first bore. A rotating shaft is rotatably installed in the first bore. A rotor frame rotates together with the rotating shaft. A polygonal mirror is secured to the rotating shaft and coupled to the rotor frame through insert molding. The polygonal mirror deflects and scans incident light. A driving source formed at the bearing and the rotor frame rotates the polygonal mirror using electromagnetic power.

Abstract: Provided are an optical scanning device and a method for detecting a synchronization signal. In the optical scanning device, a beam incident on a scanning area of an object's surface to be scanned and a beam incident on a synchronization signal detector are emitted by a light source but deflected from different deflecting surfaces of a beam deflector.

Abstract: An optical scanning unit including: a light source which produces and emits a beam; a beam deflector which deflects and scans the beam in a main scanning direction of an exposed object; and an f-? lens which corrects the beam deflected by the beam deflector at different magnifications for the main scanning direction than for a subscanning direction so that a corrected beam is focused onto the exposed object. When H is an entire length in the main scanning direction of the beam focused onto the exposed object and L is an axial distance between a reflection face of the beam deflector and the exposed object, the relationship of H and L satisfies an expression 0.25 ? H 2 · L ? 1.75 .

Abstract: Provided are an optical scanning device and a method for detecting a synchronization signal. In the optical scanning device, a beam incident on a scanning area of an object's surface to be scanned and a beam incident on a synchronization signal detector are emitted by a light source but deflected from different deflecting surfaces of a beam deflector.

Abstract: A polygonal mirror apparatus with an improved installation structure of a polygonal mirror, which is made using a plastic material, with respect to a rotor frame. The polygonal mirror apparatus includes a base, and a bearing coupled to the base and having a first bore. A rotating shaft is rotatably installed in the first bore. A rotor frame rotates together with the rotating shaft. A polygonal mirror is secured to the rotating shaft and coupled to the rotor frame through insert molding. The polygonal mirror deflects and scans incident light. A driving source formed at the bearing and the rotor frame rotates the polygonal mirror using electromagnetic power.

Abstract: An optical scanning unit including: a light source which produces and emits a beam; a beam deflector which deflects and scans the beam in a main scanning direction of an exposed object; and an f-? lens which corrects the beam deflected by the beam deflector at different magnifications for the main scanning direction than for a subscanning direction so that a corrected beam is focused onto the exposed object. When H is an entire length in the main scanning direction of the beam focused onto the exposed object and L is an axial distance between a reflection face of the beam deflector and the exposed object, the relationship of H and L satisfies an expression 0.25 ? H 2 · L ? 1.75 .

Abstract: A document feeder for a facsimile machine includes: a reading roller for a document reading unit, a shaft about which the roller rotates, a hollow rubber roller through which the shaft is located, an elastic rubber cylinder of a predetermined length mounted inside the rubber tube at the center, and a pair of levers each having a bushing to support the shaft and an eccentric cam inserted into each hole of the frames to separate the reading roller from the document reading section thereby connecting the reading roller to the frames. Brackets are attached to both ends of the document reading section to connect the document reading section to the frames. Elastic members are mounted under a center of the document reading section and support the document reading section, thereby keeping the reading roller's right and left sides in proper contact with a document reading section.